PUTREFACTION IN BLOOD. 55 



tion. It seems difficult to lower it below this amount, 

 tlie putrefaction generally stopping still. A point to de- 

 termine is, whether nitrogen is obtained from the albu- 

 minous compounds, or whether it be derived from the 

 air needftil for putrefaction. 



It will readily be seen that it is not by mere oxidation 

 caused by the oxygen of the air that carbonic acid is 

 formed; the oxygen of the air is absorbed, but what 

 becomes of it will be better known on examining the 

 liquids. Certain it is that the carbonic acid comes off in 

 overwhelming quantities, and some of it must be formed 

 by the carbon and oxygen of the organic substances them- 

 selves coming forth and leaving the residue more carbon- 

 aceous than before. It is a transfer of much of the most 

 solid elements of the blood into the atmosphere. But 

 some oxygen is absorbed, and this oxygen takes up a 

 certain quantity of carbon, which together form some of 

 the carbonic acid which escapes. We cannot distinguish 

 one part of a gas from another of the same kind ; but the 

 escape of carbonic acid on the disruption of the compound 

 after oxygen has been absorbed, leads us rather to suppose 

 that the act of oxidation had tended to liberate the gas. 

 As less oxygen is absorbed than the amount escaping in 

 carbonic acid, the whole mass of the blood must be losing 

 oxygen along with the hydrogen and its compounds, and 

 approaching a simple and inorganic form. 



It was difficult to obtain sufficient for analysis of the 

 unabsorbed residue, as there is only a smaU quantity, and 

 that small quantity is chiefly nitrogen. When 21*3 millims. 

 were obtained, it was found to consist of 



Carbonic oxide 1*03 or 4*8 per cent. 



Carburetted hydrogen 0*54 or 2-5 „ 



Hydrogen i'3 or 62 ,, 



Nitrogen i8"43 or 86'5 „ 



lOO'O 



The amount of carbonic oxide and carburetted hydrogen 



